So anyone can self identify as anything and switch around on a whim?

Technically yes, but people don’t tend to do that because identity runs deep and the trends is to correct a wrong like a mind-body mismatch.

whats the determining factor?

It’s complex but it’s usually gender dysphoria.

If I get arrested can I say I’m a female and get put in a women’s prison for instance,

You’d probably go into the prison that matches your official documentation regardless of what you say.

everyone already self identifies. the fact that most people are cis doesn’t change that fact.

the second is about procedures, and it would change from one jurisdiction to another. the real question is what ought to happen.

and think about what that means. why do we have gendered prisons, but not gendered parks? a prison surely must have more security than a public park.

Regardless of gender, if there is a prisoner who is likely to perpetrate sexual violence, then the great care needs to be taken to ensure the safety of other prisoners. Cis people are plenty capable of committing sexual assault. Trans people are far more likely to be victims of sexual violence than perpetrators of it.

Let me turn that around on you:

Should a male-presenting, gay sex offender go to a male prison or female prison? What is the purpose of gendered prisons? What problem is it trying to solve? And why are we using gender for that instead of “likely victims of the incarcerated individual”?

Gendered prisons are a ridiculous notion that only exist because our prison system itself is completely fucked up, profit-driven, and inhumane. It produces worse outcomes than almost any other form of legal consequences except in extreme cases.

Are you a woman?

at least you bring forward an actual argument.

i’ve seen so many transphobes who just say “god didn’t want it” and that’s the end of the story. we need more discussion in our world, and we need good arguments; even if i don’t agree with you.